Process and apparatus for the preparation of dental models

Abstract

An apparatus and a method for use in dental reconstruction work in the production of cast dental models and dental dies includes a U-shaped base member having a negative cavity in its top planar surface and a complementary U-shaped member in the form of horizontally disposed plate having a series of cast dowel-like members in the form of a dental arch depending from one surface of said plate and adapted for slidable reception in the negative cavity of said U-shaped base member. The other surface of said horizontally disposed plate of said complementary U-shaped member contains a series of anchoring means which may be embedded in the unset dental stone of a positive dental model. The use of the complementary U-shaped member with its anchoring means anchored in the set dental stone of the positive dental model allows for a die to be sawed out and separated from the remainder of the model while the rest of the positive model can be permanently and positively placed in the negative cavity of said base so as to allow the die to be removed and replaced into proper position with the adjacent teeth of the model for proper use on an articulator.

I claim: 
     
       1. A two-piece device for use in dental reconstruction work in the production of cast dental models from dental stone which comprises: A. a reusable U-shaped base member including: 1. exterior walls containing accurately-spaced indicia;   2. a top planar surface;   3. a negative cavity in said top planar surface, conforming generally to the shape of a dental arch and having interior walls containing vertically-disposed ridges and grooves;     B. a complementary disposable U-shaped member in the form of a horizontally-disposed plate having exterior side walls and including: 1. a series of cast solid dowel-like members in the form of a simulated dental arch depending from one surface of said plate; a. said dowel-like members being formed by alternate vertical ridges and grooves,   b. said vertical ridges and grooves of said dowel-like members slidably mating with the vertically-disposed ridges and grooves of the negative cavity of said reusable U-shaped base member, and   c. said horizontally-disposed surface of said plate snugly fitting against the planar surface of said base member;     2. anchoring means on the other surface of said horizontally-disposed plate for positively bonding of said plate with the unset stone of said cast dental model; and   3. accurately-spaced indicia on said side walls, which match the indicia of the side walls of said base member.     
     
     
       2. A device, as defined in claim 1, in which: A. the interior walls of said negative cavity of said base member taper inwardly, and   B. the cast solid dowel-like members taper inwardly from top to bottom at the same angle as the taper of the walls of said negative cavity.   
     
     
       3. A device, as defined in claim 1, in which the vertical grooves on either side of the dowel-like member do not completely meet. 
     
     
       4. A device, as defined in claim 1, in which said spaced indicia involve color. 
     
     
       5. A device, as defined in claim 1, in which said indicia involve scribe marks. 
     
     
       6. A device, as defined in claim 1, in which said anchoring means include inwardly turned walls. 
     
     
       7. A device, as defined in claim 1, in which said anchoring means include a series of raised projections. 
     
     
       8. A method of making a positive dental model with removable die sections from a dental impression which comprises the steps of: A. pouring dental stone into said dental impression,   B. placing a disposable U-shaped plate member having exterior side walls marked with accurately-spaced indicia, anchoring means on one planar surface and a series of depending solid dowel-like members cast in the form of vertical ridges and grooves in the general shape of a simulated dental arch on the other planar surface, anchoring means down into the unset stone;   C. allowing said dental stone to set;   D. separating the dental positive model and said U-shaped plate member embedded therein from said negative impression;   E. providing a reusable U-shaped base member having a negative cavity of complementary shape to said simulated dental arch of said dowel-like members, having interior walls which contain complementary ridges and grooves for engagement with the ridges and grooves of said dowel-like members and exterior walls with accurately-spaced indicia marked thereon, which match the indicia of the walls of said disposable U-shaped plate member;   F. marking lines along the positive model for the required die or dies requiring restoration work;   G. sawing the positive model along the mark lines to separate the die from the positive model;   H. matching the indicia of the walls of said disposable plate with the indicia of the walls of said reusable base member;   I. sliding the positive model, absent the sawed-out dies, into the negative cavity of said base member and engaging the ridges and grooves of said simulated dental arch of said dowel-like members with the complementary ridges and grooves of said negative cavity of said base member;   J. performing the required work on the removed dies;   K. matching the indicia on the wall of the die with the indicia of the reusable base member; and   L. replacing the reworked die in the base in proper juxtaposition to the original teeth of the positive model.   
     
     
       9. A method of making a positive dental model, as defined in claim 8, the improvement of: A. sliding said simulated dental arch of dowel-like members into said negative cavity of said base member and engaging the ridges and grooves of said simulated dental arch of said dowel-like members with the complementary ridges and grooves of said negative cavity of said base member; and   B. removing the positive model, including the depending dowel-like members from the base member and sawing along the marked lines to separate the die from the positive model.